56 



THE DICTIONARY OF GARDENING, 



Fear continued. 



from the soil up the tree, by a belt of sticky material 

 round the tree-trunk. If the tree is trained, the wall, 

 or the support, should also have a belt of the same 

 substance. The larvae of the butterflies, and of the 

 larger moths, should be picked off and destroyed. The 

 larvae of the Tortrices and Geometers may be either 

 picked off or shaken into an old sheet, or other cloth, 

 and should be swept up and destroyed at once. Leaf- 

 miners can be killed by pressure with finger and thumb, 

 but the harm done by them is, as a rule, too 

 slight to render this labour necessary. Certain 

 Sawflies are very hurtful to fruit-trees, and, 

 among others, to the Pear-tree. The worst of 

 these foes is the Slugworm, or larva of Erio- 

 campa limacina. For an account of the injuries 

 done by it, and remedies, see Slngworms. 



Mr. Buckton, in his " Monograph of British 

 Aphides," mentions Aphis pyraria and A. lenti- 

 ginis as obtained by him from Pear-trees in 

 England, and says that the former was so 

 abundant on one tree as to entirely cover it with 

 excretions. Other kinds have been recorded 

 by various entomologists. All the Aphides may 

 be treated in the same way. See Aphides. 

 To the allied genus Psylla belong several spe- 

 cies that feed on the Pear, and the following 

 have been recorded from Britain : P. pyri- 

 suga, Forst., P. apiophila, P. pyricola, and 

 P. rimulans. 



Fear continued. 



Mitea, which give rise to blistered spots in them (see 

 Fig. 60). These blisters are small, and, at first, yellowish 

 or red; but, in a short time, they tend to become 

 brown, and then they dry up, and fall out of the 

 leaf, if pressed on, while the rest of the leaf may still 

 be apparently healthy. Very often, the blisters are so 

 numerous that many of them unite, and the leaf may 

 become covered with them over almost the whole sur- 

 face. In severe cases, almost every leaf on a tree may 



Fio. 58. PSYLLA PYRISUOA (the Line below the 

 Insect shows the natural length). 



Of these, P. pyrisuga (see Fig. 58) is probably 

 the most hurtful. In Ormerod's "Manual," 

 it is named P. Pyri, Schmidb., and is also 

 called the Pear Sucker. The female is Hn. 

 long, and is not very unlike a Frog Hopper 

 in form ; but the wings are transparent. It is able to 

 leap considerable distances, by means of the large thighs 

 of the hindmost pair of legs. It is usually at first of a 

 greenish colour, with red eyes; but it becomes, in a 

 short time, variegated with carmine-red, brown, and 

 black, and these colours extend to the base of the 

 wings, and to the legs. The insects live on juices of 

 the plants they infest, drawing them in through a beak, 

 which, when at rest, lies close against the breast. The 



Fro. 60. PEAR-LEAF ATTACKED BY PIIYTOPTUS PYRI a, Leaf recently 

 attacked by Mites ; 6, Leaf with old Mite Galls. 



be more or less injured, and many of them destroyed, 

 so that the trees are much weakened. Moreover, the 

 animals shelter themselves in the buds in winter, and 

 a tree, when once infected, continues to suffer year 

 after year. A microscopic examination of a section taken 



Fio. 59. LARVA OF PSYLLA PYRISUGA (the Line shows the 

 natural length). 



male is about &in. long. The larvae (see Fig. 59) and 

 pupae, as well as the mature insects, live upon Pear-trees, 

 and, occasionally, upon Apple-trees also. They suck the 

 juices from the leaves, and from the young shoots, and dis- 

 charge their sticky excretions over all parts of the trees. 

 They are thus hurtful both by withdrawing the sap, and 

 by clogging the surfaces of leaves and twigs, so that 

 these parts are unable to assist in nourishing the plant. 

 The mature insects usually pass the winter sheltered in 

 crevices under bark, &c. A remedy found serviceable 

 is to apply tobacco infusion, soapsuds, or the other solu- 

 tions employed against Aphides (which see). 



Pear leaves are sometimes severely injured by Gall 



FIG. 61. BLISTER FORMED ON LEAF BY PHYTOPTUS PYRI 

 a, Opening of Gall; p, Tissue of Leaf altered by Mites; 

 , Egg of lUite. 



from a blister (see Fig. 61) shows that the cells in the 

 middle of the leaf become torn asunder, so as to leave 

 air-spaces larger than before ; and the surfaces of the 

 leaf are thus pushed farther apart. In the middle of the 

 blister, on its lower surface, is a small opening, which 

 permits the Mites to pass out of the blister. These 

 animals are named Phytoptus Pyri. See Mites. 



It is so difficult to completely effect a remedy, that it 

 is not advisable to give the labour, save in the case of 

 trees of peculiar value ; and it is preferable to burn the 

 diseased trees, to prevent the evil spreading. To destroy 

 the Mites, the most successful course is, at the moment 



